Edit post

Edit your reply below.

Post Body
Enter your post below.
Actually, there are four positions on a retainer: direct release, low pressure, high pressure, and slow direct release. The slow direct release allows a full release, but only after a period of time has elapsed; this is intended to eliminate a stop to turn the retainers down after reaching the bottom of the grade. This was covered in the Air Brake story in April TRAINS . . .
Tags (Optional)
Tags are keywords that get attached to your post. They are used to categorize your submission and make it easier to search for. To add tags to your post type a tag into the box below and click the "Add Tag" button.
Add Tag